Association of blood pressure and coronary collateralization in type 2 diabetic and nondiabetic patients with stable angina and chronic total occlusion.

OBJECTIVE: We investigated whether and to what extent blood pressure (BP) affects coronary collateralization in type 2 diabetic and nondiabetic patients with stable angina and chronic total occlusion.
METHODS: Brachial BP was measured using an inflatable cuff manometer in 431 diabetic and 287 nondiabetic patients with stable angina and angiographic total occlusion of at least one major coronary artery. They were classified according to the SBP (<100, 100-119, 120-139, 140-159, 160-179, and ≥180 mmHg), DBP (<60, 60-69, 70-79, 80-89, 90-99, and ≥100 mmHg), and pulse (<40, 40-49, 50-59, 60-69, 70-79, and ≥80 mmHg) BP ranges. The degree of coronary collaterals supplying the distal aspect of a total occlusion from the contralateral vessel was graded as poor (Rentrop score of 0 or 1) or good collateralization (Rentrop score of 2 or 3).
RESULTS: In diabetic patients, the incidence of poor collateralization was related to the DBP in a U-shaped pattern, with the lowest risk at 80-89 mmHg. In nondiabetic patients, an optimal DBP range was 90-99 mmHg for good collaterals, but no U-shaped relation between DBP and coronary collateralization was observed. After adjusting for the baseline characteristics in the logistic regression models, the increased risk of poor collateralization persisted for low or high DBP ranges in diabetic [odds ratio (OR) 2.02-7.29, P ≤ 0.04] and nondiabetic patients (OR 3.62-5.98, P ≤ 0.02). No such relations were observed between collateral grades and SBP and pulse BP.
CONCLUSION: This study demonstrates that 80-89 and 90-99 mmHg are the optimal ranges for DBP in diabetic and nondiabetic patients with stable angina and chronic total occlusion, within which the risk of poor collateralization is low.